# Orphan Block 1. [[Block(s)|Blocks]] that are [[Mining|mined]] a little late and don’t form part of the main [[Blockchain|blockchain]]. In [[Bitcoin (blockchain)]] these are called ‘orphans’ and are entirely discarded, but in [[Ethereum (blockchain)]] they are called ‘[[Uncle|uncles]]’ and can be referenced by later blocks. 3. Blocks whose parent [[Block(s)|block]] has not been processed by the local [[Node(s)|node]], so they can’t be fully validated yet. Synonyms: Orphan block Not To Be Confused With: Stale block. 5. Orphan describes a [[Block(s)|block]] that has been abandoned and will not be built upon. Blockchain is technology for creating permanent, secure digital recordings. If you imagine the [[Blockchain|blockchain]] as a book of records, then each page in that book is what is known as a “[[Block(s)|block]]”. A [[Block(s)|block]] is simply a recording of information. Blocks are attached to each other making what is known as the blockchain. Because many computers are maintaining the blockchain, occasionally two [[Block(s)|blocks]] are created at the same time. Since only one block can be created at a time, only one will be continued and built upon, the other block will be abandoned and is known as an orphan.